Sectional conduit.



UNITED raras PATENT OFFICE. i

VILLIAM L. MCGOWAN, OF PHILADELPHIA, PENNSYLVANIA.

SECTIONAL CoNDUlT.

srnorsrcarron forming' part ofnetters Patent No. 712,839, dated November 4, 1902.

Application filed March 20,1902. Serial No. 99,235. (No model.)

To all whom, t Netty concern:

Be it known that I, WILLIAM L. McGowan, of Philadelphia, PhiladelphiaJ county, Pennf sylvania, have invented an Improvement in Sectional Conduits, of which the following is a specification.

More particularly, my invention relates to the means for uniting the ends of adjacent conduit-sections together to keep the sections in alinement and form a strong joint capable of sustaining the transverse strains to which the sections may be subjected.

The walls of the conduit-sections arepr'ovided with centering-holes which usually ex tend longitudinallythrough theentire section, and it has been customary to unite adjacent sections together by dowel-pins extending partly into the holes of each section. Owing to the liability of the doWel-pins to slip or Work longitudinally in the holesof one section,

and thus become disengaged from vthe hole of the other section, it is necessary to provide some means to hold thedoWel-pins against the longitudinal movement. It also frequently occurs that in terra-cotta or other baked conduitjsections the centering hole or holes in one section shrink to a diameter too small to admit the dowel-pin, which, under existing methods, requires the hammering down of one end of the dowel-pin to a diameter small enough to enter the shrunken centering hole or socket. This is objectionable and requires considerable labor and causes delay in the laying of the conduit. lVith the ordinarycylinvdrical dow'el-pin commonly used there is nothing When'a single pin is nsedto prevent the turning of one section on its Aaxis with reference to the other, which is liable to occur if the bed settles unevenly or is undermined, or if the weight on the surface is unequally distributed. Such turning of one section with reference to another not only causes injury to the walls of the conduit, frequently resulting in fracture, but often damages the cables contained in the conduit-ducts.

It is one of the objects -of my invention to prevent the longitudinal movement of the dowel-pin within the dowel-socket of one section and its resulting'disengagement from the dowel-socket of the other section. This object I accomplish by the employment of a dowel-pin retainer fitting the dowel-socket of one or both'sections and provided with a stop or projection which prevent-s the inward lmovement of the dowel-pin.

It is another object of my invention to enable a section havinga shrunken dowel socket 'or hole to be united with one having a socket of normal size without the necessity of hammering down the dowel-pin to reduce its diameter. This result I accomplish by using the dowel-pin retainer only in vthe doWel-socket of full diameter and allowing the dowel-pin, without the retainer to project directly into the shrunken socket of the other section.

Y It is another object of vmy'invention to prevent the turning of the dowel-pin in its socket and also the turning of one section with referenceto another when a single dowel connection is employed. This object 1 accomplish Vby employing a dowel-pin of square or other 'non-circular form, which may be used, so far as this feature alone is concerned, either with or Without the dowel-pin retainer.

In the drawings, Figure 1 is a'perspective view of a conduit-section, illustrating my improved dowel-pin union. Fig. 2 is a longitudinal vertical sectional view of two sections taken on the line 2 2 of Fig. .1 and showing the union.l Figs. 3 and 4 are 'perspective views illustrating different forms ofthe dowel and retainer. Figs. 5 and 6 are perspective views illustrating different forms of the "doWel-pin retainer, and Fig. 7 is an enlarged sectional View of the union between two sections,

The walls of the cond uit-'sections a are pro- -vided with longitudinal centering-holes b, which usually extend entirely through the section and the ends of which constitute dowel sockets. It has been customary to unite adjacent sections by dowel-pins projecting part way into the doWel-sockets of each section. Instead of thus inserting the dowel-pins directly in the dowel-sockets I employ dowel-pin retainers c, which are inserted in the sockets b and receive the dowelpins. The normal diameter of the sockets b is made suiiciently large to receive both the retainer and pin. The retainers c are iiauged or provided with lugs at their outer ends, so

as to be retained against inward movement ICO in the sockets b, and the rims of the sockets l) are preferably countersunk, as at d, to receive the tianges c of the retainers, which thus form no obstruction to the meeting of the ends of the sections a a. The retainers c are closed or flanged at their inner ends, as atf, to form retaining-stops for the dowelpins g.

Ordinarily in practice a retainer c willbe inserted in the socket b of each of the sections. The dowel-pin g will then be inserted in one ot the retainers and will project from the end of the section, as shown in Fig. I. The other section will then be placed against the first section and the projecting end of the dowelpin will fit in the other retainer. The retainer will thus prevent longitudinal movement and disengagement of the dowel-pin. In those cases, however, where the retaining hole ol socket b of one section has shrunken, so that the retainer-and dowel together' cannot be inserted, the retainer is omitted from the shrunken socket, which will, however, be of suiiicient size to receive the dowel-pin without the necessity of decreasing its diameter. I have shown this construction in the dowel-pin union at the top and bottom of Fig. 2. Vhile this will hold the dowel-pin against longitudinal movement in one direction only and is therefore not as eicient as where retainers are used for both ends, it will ordinarily be sufficient, particularly if the retainer is used with the section which is laid first, as that retainer will h old the dowelpin against inward movement while the next section is being laid. The dowel-pin may be prevented from slipping into the socket by rst placing a little cement therein where it is inconvenient to use the retainer.

The number of dowel-pins used in making a joint between two sections may be varied. In some cases a single dowel is sufiicient, while in others as many as tive may be used, as shown in Fig. 1, or more, it desired.

While the dowel-pin and its retainers may be cylindrical in shape, as illustrated in Fig. 3, I prefer to make them of square or other non-cylindrical shape, as shown in Fig. 4, in which case the sockets ZJ should preferably be correspondingly shaped. The advantage of making the dowel-pin and its retainers non-cylindrical is not only that it prevents the dowel and retainer turning in the centering hole or socket, which, as has been explained, is liable to cause injury, but also that where a single dowel-pin is used between adjacent sections it prevents one section turning with reference to the other.

In Figs. 3, 4, and 7the retainers are shown in the form ot' socket-pieces Vadapted to receive and inclose one end of the dowel-pin. They may, however, be made in the formof a strap open on the sides, as shown in Fig. 5, or a single strip oppositely flanged on its ends, as shown in Fig. 6, may be used. An-

other advantage of my construction is that the ends of the sections may be cut olf when required without affecting their utility, as would be the case if the dowel-sockets were provided with internal retaining stops or shoulders for the ends of the dowel-pins, because in that case the cutting off of the end 4ot the section would render the dowel-sock ets too short or totally destroyed.

The details of construction shown may be Varied without departing from the invention.

What I claim as new, and desire to secure by Letters Patent, is as follows:

1. In a sectional conduit, the combination with the abutting sections provided on their ends with dowel-sockets, of a dowel-pin projecting part way into the socket of each section, and a dowel-pin retainer supported in one of said dowel-sockets and provided atits inner end with a retaining-stop to prevent inward movement of the dowel-pin.

2. In a sectional conduit, the combination with the abutting sections provided on their ends with dowel-sockets, of a dowel-pin projeeting part way into the socket of each section, and a dowel-pin retainer supported in each of said dowel-sockets and .provided at its inner end with a retaining-stop to prevent inward movement of the dowel-pin in either direction.

3. In a sectional conduit, the combination with the abutting sections provided on their ends with dowel-sockets, of a dowel-pin projecting part way into the socket of each section and a dowel-pin retainer supported in one of said dowel-sockets and provided at its outer end with a projection to prevent inward movement of said retainer in the socket, and at the inner end with a retaining-stop to prevent inward movement of the dowel-pin.

4. In a sectional conduit, the combination with the abutting sections provided on their ends with dowel-sockets, of a dowel-pin projecting part way into the socket of each section and a dowel-pin retainer supported in one of said dowel-sockets and provided atits outer end with a projection to prevent inward movement of said retainer in the socket, and at the inner end with a retaining-stop to prevent inward movement of the dowel-pin, the outer end of the socket being recessed to receive the retaining projection of said dowel-pin retainer.

5. In a sectional conduit, the combination with the abutting sections provided on their ends with non-circular dowel-sockets, and non-circular dowel-pins extending part way into the socket of each section, and a dowelpin retainer supported in one of said sockets and provided at its inner end with a retainin g-stop, whereby rotation of one section with reference to the other is prevented and the dowel-pin is held against inward movement by said retainer.

6. The combination with the dowel-pin, of a dowel-pin retainer adapted to be inserted in the socket of a conduit-section provided with means to hold the dowel-pin against inward movement.

ICO

IIO

7. The combination with the dowel-pin, of a doweI-pin retainer adapted to be inserted in the socket ot` a conduit-section provided at its outer end with a flange or projection c and at its inner end with a stop f.

8. The combination with the tubular dewelpin retainer havingv a stopfat its inner end, ofthe dowel-pin tting within said retainer for a portion of its own length and held against inward movement by the stop f.

9. The combination with the tubular noncircular dowei-pin retainer having a stop f at its inner end, of the non-circular dowelpin fitting within said retainer for a portion against inward movement by the stop f.

In testimony of which invention I have hereunto set my hand.

WILLIAM L. MCGOWAN. Witnesses:

R. M. HUNTER, R. M. KELLY. 

